Well, the tests performed used ramps and truck scales to plot the down force at the drooped tires.
The plots showed what you would logically expect to see: The packs would be progressively harder to bow as you bow them to get droop....and, if they don't have to bow as much, for the same amount of droop, there is less resistance for that amount of droop.
The longer the shackle, the further down the tire could drop before the pack's bowing pulled back up at it...and, for any given amount of droop, the pack didn't have to bow as much for a longer shackle.
The Revolvers simply acted as longer shackles, and, therefore, allowed more droop before the pack had to bow.
The coil sprung rigs allowed droop to continue without pulling back up on the dropping side...as there was no connection between the coil and the frame/axle to pull on it.
When a coil sprung rig was drooped enough to relax the coil, there was still down force....as the higher side leveraged the dropped side down. The down force smoothly transitioned during the droop, because the coil's down force contribution was negligible compared to the leverage contribution.
This also dispelled/disproved another myth about coil springs. One myth was that once the coil was no longer in contact/pushing down the drooped side axle, the tire would have no down force. In fact, the down force was similar with or without the coil, as the leverage action was the primary force.
This is the same for a live axle with leaves...its the leverage, not the pack or shackles, that is pushing the tire down when drooped.
The same myth was applied to revolvers as to coils, due to the same lack of understanding of how they worked...and repeated ad nauseam by those who heard it and believed it, spreading the misunderstandings.
When the tests involved teeter boards and ramps, they also showed what would be logically expected. Gravity pulls things down, and, a rig's center of gravity is what is acted upon.
So, if you have a board, and, put a toy truck on it, and tilt it, the truck rolls down the board.
If you chock the front tires, and repeat the experiment, so the truck can't roll down the board, you will reach a point at which the truck can somersault over its front tires.
This angle will be the angle that puts the truck's COG FORWARD of the front tires. It will not flip until the COG is passed that point.
If you changed the truck's tires to taller ones, it would raise its COG, and, decrease the angle needed to get that higher COG ahead of the tires.
If the toy truck had a suspension, for the same height, etc, the COG would not be different, and the angle required to flip it would not change.
If the truck had a coil suspension, tilting it enough can make it lean forward, as the front end compresses. This tends to lift the rear. If the COG point is more to the rear, this would raise the COG point. If the COG point is more to the front, this would lower the COG point. Typically, tilting a rig to go down a steep hill puts more weight to the front.
This unweights the rear. Coil sprung rigs have the sprung weight supported on the coil. If the rig is not about to flip, gravity makes the sprung weight rest on SOMETHING.
As the coil sprung rig is progressively tilted down, at some point, the COG is forward enough to flip it...and, the coil sprung rig will go over.
So will any other rig...including rigs with leaf sprung suspensions. Essentially, gravity exerts the same forces, and doesn't care if you have coils, leaves or t-bars, etc.
Where the confusion seemed to be based was illustrated by the way any flexy suspension tended to allow more body motion. For a analogous scenario, consider being off camber/side hilling.
If your rig is stiffly sprung, so it rides with little lean in turns, when side hilled, your roof will be more parallel to the slope, because your D and P side suspensions are at ~ equal travel.
If your rig is softly sprung, the down hill side might be very compressed...leaning you to the down hill side more.
The UPhill side will tend to be ~ ride height in travel if its still supporting the weight of the rig it normally does.
If the COG tilts out past the line of the downhill tires, over you go.
So, on a steep slope, its more about the suspension's stiffness or softness...and if its letting your downhill side compress enough to be a problem.
The UPHILL side is not "Holding you down"....whatever weight the rig is supporting on that side is being supported....not anchored. Its the DOWNHILL side that pulls you over, when the COG passes the down hill tires. (As then there's no weight FOR the uphill side TO support).
So, a coil sprung jeep for example is not more likely to do an end over or side roll than a leaf sprung jeep, for the same COG, etc. A leaf pack doesn't magically hold down the jeep.
A more softly sprung rig is more likely to suffer from weight transfer related to body lean, regardless of if it has coils or leaves.
The tests found that the conditions associated with soft suspensions were exacerbated by taller lifts in the above scenarios.
Some jeeps for example used soft/off road anti-roll bars (Curie, etc) to help with off camber scenarios for example, to help reduce the off camber lean.
Much of the confusion essentially was due to blaming the revolvers for soft suspension and tall lift/high COG characteristics...as its not unusual for many changes to be installed in conjunction with each other.
Back to back runs with revolvers and long shackles for example did not show any increased forward weight transfer/"unloading" on steep down hills. The revolvers typically resulted in a lower rear ride height, which improved, rather than worsened, front lean.
Coil sprung rigs also showed no "unloading"....they worked the same as leaf sprung rigs as far as the suspension, merely supporting the rig's weight, not holding the rig down.
Once people understand that the suspension supports weight, and doesn't hold the weight down onto itself....the rest falls into place.
The "coils not touching the bucket means the tire is not pushed onto the ground" crowd is loud and numerous...and, are under the same misunderstanding as the "Revolvers are just for show, because the tires are not pushed down" crowd, which is equally loud, numerous, and wrong.
The plots showed what you would logically expect to see: The packs would be progressively harder to bow as you bow them to get droop....and, if they don't have to bow as much, for the same amount of droop, there is less resistance for that amount of droop.
The longer the shackle, the further down the tire could drop before the pack's bowing pulled back up at it...and, for any given amount of droop, the pack didn't have to bow as much for a longer shackle.
The Revolvers simply acted as longer shackles, and, therefore, allowed more droop before the pack had to bow.
The coil sprung rigs allowed droop to continue without pulling back up on the dropping side...as there was no connection between the coil and the frame/axle to pull on it.
When a coil sprung rig was drooped enough to relax the coil, there was still down force....as the higher side leveraged the dropped side down. The down force smoothly transitioned during the droop, because the coil's down force contribution was negligible compared to the leverage contribution.
This also dispelled/disproved another myth about coil springs. One myth was that once the coil was no longer in contact/pushing down the drooped side axle, the tire would have no down force. In fact, the down force was similar with or without the coil, as the leverage action was the primary force.
This is the same for a live axle with leaves...its the leverage, not the pack or shackles, that is pushing the tire down when drooped.
The same myth was applied to revolvers as to coils, due to the same lack of understanding of how they worked...and repeated ad nauseam by those who heard it and believed it, spreading the misunderstandings.
When the tests involved teeter boards and ramps, they also showed what would be logically expected. Gravity pulls things down, and, a rig's center of gravity is what is acted upon.
So, if you have a board, and, put a toy truck on it, and tilt it, the truck rolls down the board.
If you chock the front tires, and repeat the experiment, so the truck can't roll down the board, you will reach a point at which the truck can somersault over its front tires.
This angle will be the angle that puts the truck's COG FORWARD of the front tires. It will not flip until the COG is passed that point.
If you changed the truck's tires to taller ones, it would raise its COG, and, decrease the angle needed to get that higher COG ahead of the tires.
If the toy truck had a suspension, for the same height, etc, the COG would not be different, and the angle required to flip it would not change.
If the truck had a coil suspension, tilting it enough can make it lean forward, as the front end compresses. This tends to lift the rear. If the COG point is more to the rear, this would raise the COG point. If the COG point is more to the front, this would lower the COG point. Typically, tilting a rig to go down a steep hill puts more weight to the front.
This unweights the rear. Coil sprung rigs have the sprung weight supported on the coil. If the rig is not about to flip, gravity makes the sprung weight rest on SOMETHING.
As the coil sprung rig is progressively tilted down, at some point, the COG is forward enough to flip it...and, the coil sprung rig will go over.
So will any other rig...including rigs with leaf sprung suspensions. Essentially, gravity exerts the same forces, and doesn't care if you have coils, leaves or t-bars, etc.
Where the confusion seemed to be based was illustrated by the way any flexy suspension tended to allow more body motion. For a analogous scenario, consider being off camber/side hilling.
If your rig is stiffly sprung, so it rides with little lean in turns, when side hilled, your roof will be more parallel to the slope, because your D and P side suspensions are at ~ equal travel.
If your rig is softly sprung, the down hill side might be very compressed...leaning you to the down hill side more.
The UPhill side will tend to be ~ ride height in travel if its still supporting the weight of the rig it normally does.
If the COG tilts out past the line of the downhill tires, over you go.
So, on a steep slope, its more about the suspension's stiffness or softness...and if its letting your downhill side compress enough to be a problem.
The UPHILL side is not "Holding you down"....whatever weight the rig is supporting on that side is being supported....not anchored. Its the DOWNHILL side that pulls you over, when the COG passes the down hill tires. (As then there's no weight FOR the uphill side TO support).
So, a coil sprung jeep for example is not more likely to do an end over or side roll than a leaf sprung jeep, for the same COG, etc. A leaf pack doesn't magically hold down the jeep.
A more softly sprung rig is more likely to suffer from weight transfer related to body lean, regardless of if it has coils or leaves.
The tests found that the conditions associated with soft suspensions were exacerbated by taller lifts in the above scenarios.
Some jeeps for example used soft/off road anti-roll bars (Curie, etc) to help with off camber scenarios for example, to help reduce the off camber lean.
Much of the confusion essentially was due to blaming the revolvers for soft suspension and tall lift/high COG characteristics...as its not unusual for many changes to be installed in conjunction with each other.
Back to back runs with revolvers and long shackles for example did not show any increased forward weight transfer/"unloading" on steep down hills. The revolvers typically resulted in a lower rear ride height, which improved, rather than worsened, front lean.
Coil sprung rigs also showed no "unloading"....they worked the same as leaf sprung rigs as far as the suspension, merely supporting the rig's weight, not holding the rig down.
Once people understand that the suspension supports weight, and doesn't hold the weight down onto itself....the rest falls into place.
The "coils not touching the bucket means the tire is not pushed onto the ground" crowd is loud and numerous...and, are under the same misunderstanding as the "Revolvers are just for show, because the tires are not pushed down" crowd, which is equally loud, numerous, and wrong.
